This site is 100% ad supported. Please add an exception to adblock for this site.

Science IIA- Exam 1


undefined, object
copy deck
physical changes:
crumple, crush, boil- does not change the chemical composition.
chemical changes:
ferment, rust, explode, oxidize- changes the chemical composition.
states that mass is neither created nor destroyed during a chemical reaction.
law of conservation of mass
Heterogeneous mixture
does NOT blend both substances all the way together- sand/water mixture.
Homogenous mixture
blends both substances together- salt/water mixture, solutions.
separates substances on the basis of the boiling points of the substances.
separates by formation of solid, pure particles from a solution.
separates substances based on their movemtn through a special paper.
separates solids from liquids by using a porous barrier.
a substance that cannot be separated into simpler substances by physical or chemical means.
a chemical combination of two or more different elements
what are the horizontal rows in the periodic table called?
what are the vertical columns in the periodic table called?
groups or families
states that regardless of the amount, a compound is always composed of the same elements in the same proportion by mass.
Law of definite proportions.
equation of the law of definite proportions?
mass percentage of an element (%) = mass of element/mass of compound x 100%
The Law of multiple proportions
if separate elements form 2 different compounds, the different masses of Y that combine with a fixed mass of X can be expressed as a ratio of small whole numbers.
proposed the nuclear atomic model
Determined the mass-to-charge ratio of an electron
where is a proton located?
in the nucleus.
what is a proton's charge and mass?
+1, 1
where is a neutron located?
in the nucleus.
what is a neutron's charge and mass?
0, 1
where is an electron located?
in the space surrounding a nucleus.
what is an electron's charge and mass?
-1, 1/1840
The number of protons in an atom is referred to as its?
atomic number
atomic number is equal to the number of _____ in an atom?
The number of _____ in an atom identifies it as an atom of a particular element.
Most atoms have what kind of charge?
they're neutral.
atomic number=
mass number=
electrons + protons + neutrons
One amu (atomic mass unit) is
1/12 the mass of a carbon-12 atom.
The atomic mass of an atom is usually not a whole number because it accounts for
both the relative abundance and the mass of each of the atom's isotopes.
the force that holds two atoms together.
chemical bond
electrons on the outermost energy level
valence electrons
a positively charged ion
negatively charged ion
defined atoms, started the study of atoms, most of his ideas are no longer supported.
influential philospher, believed Democritus' ides were incorrect and tried to disprove him.
John Dalton
atomic theory, most of his ideas were correct and still believed today.
electron configurations
1s2, 2s2...

Deck Info